Gas prices are seen in Washington, D.C., with the Capitol in the background.
President Bush temporarily suspends environmental rules on gasoline that have been blamed for a recent spike in gas prices. The change may make it easier for refiners to meet demand as the nation makes its holiday travel plans.
Analysts say that Tuesday's change may bring lower prices by removing a requirement that refiners mix gasoline with ethanol and other additives in order to meet clean-air standards. The process, which refineries usually institute at the start of each summer, has been blamed for tightening the supply of gas, helping prices rise.
The president also halted the purchase of crude oil for the government's emergency reserve until after the summer. That change is unlikely to have an impact on gas prices, which experts expect to stay high through the summer.